I made 2 orders using this code, one was processed, got this email regarding the second order:
Thank you for placing your order with Charles Tyrwhitt.
I am contacting you regarding the $15 ‘Thank You’ voucher and the free tie offer used on your recent orders. One of the terms and conditions of the offers is that they may only be used once. Our records show that the voucher as well as the tie offer has been used on a previous order therefore it will not be possible to redeem the offers on order w36099234.
I would be grateful if you would contact us to advise as to how you would like to proceed.
BTW I don't know what he's talking about with the tie, I never got any for free...